1 //===--- ToolChain.cpp - Collections of tools for one platform ------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "Tools.h"
11 #include "clang/Basic/ObjCRuntime.h"
12 #include "clang/Driver/Action.h"
13 #include "clang/Driver/Driver.h"
14 #include "clang/Driver/DriverDiagnostic.h"
15 #include "clang/Driver/Options.h"
16 #include "clang/Driver/SanitizerArgs.h"
17 #include "clang/Driver/ToolChain.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/StringSwitch.h"
20 #include "llvm/Option/Arg.h"
21 #include "llvm/Option/ArgList.h"
22 #include "llvm/Option/Option.h"
23 #include "llvm/Support/ErrorHandling.h"
24 #include "llvm/Support/FileSystem.h"
25 using namespace clang::driver;
26 using namespace clang;
27 using namespace llvm::opt;
28 
29 static llvm::opt::Arg *GetRTTIArgument(const ArgList &Args) {
30   return Args.getLastArg(options::OPT_mkernel, options::OPT_fapple_kext,
31                          options::OPT_fno_rtti, options::OPT_frtti);
32 }
33 
34 static ToolChain::RTTIMode CalculateRTTIMode(const ArgList &Args,
35                                              const llvm::Triple &Triple,
36                                              const Arg *CachedRTTIArg) {
37   // Explicit rtti/no-rtti args
38   if (CachedRTTIArg) {
39     if (CachedRTTIArg->getOption().matches(options::OPT_frtti))
40       return ToolChain::RM_EnabledExplicitly;
41     else
42       return ToolChain::RM_DisabledExplicitly;
43   }
44 
45   // -frtti is default, except for the PS4 CPU.
46   if (!Triple.isPS4CPU())
47     return ToolChain::RM_EnabledImplicitly;
48 
49   // On the PS4, turning on c++ exceptions turns on rtti.
50   // We're assuming that, if we see -fexceptions, rtti gets turned on.
51   Arg *Exceptions = Args.getLastArgNoClaim(
52       options::OPT_fcxx_exceptions, options::OPT_fno_cxx_exceptions,
53       options::OPT_fexceptions, options::OPT_fno_exceptions);
54   if (Exceptions &&
55       (Exceptions->getOption().matches(options::OPT_fexceptions) ||
56        Exceptions->getOption().matches(options::OPT_fcxx_exceptions)))
57     return ToolChain::RM_EnabledImplicitly;
58 
59   return ToolChain::RM_DisabledImplicitly;
60 }
61 
62 ToolChain::ToolChain(const Driver &D, const llvm::Triple &T,
63                      const ArgList &Args)
64     : D(D), Triple(T), Args(Args), CachedRTTIArg(GetRTTIArgument(Args)),
65       CachedRTTIMode(CalculateRTTIMode(Args, Triple, CachedRTTIArg)) {
66   if (Arg *A = Args.getLastArg(options::OPT_mthread_model))
67     if (!isThreadModelSupported(A->getValue()))
68       D.Diag(diag::err_drv_invalid_thread_model_for_target)
69           << A->getValue() << A->getAsString(Args);
70 }
71 
72 ToolChain::~ToolChain() {
73 }
74 
75 const Driver &ToolChain::getDriver() const {
76  return D;
77 }
78 
79 bool ToolChain::useIntegratedAs() const {
80   return Args.hasFlag(options::OPT_fintegrated_as,
81                       options::OPT_fno_integrated_as,
82                       IsIntegratedAssemblerDefault());
83 }
84 
85 const SanitizerArgs& ToolChain::getSanitizerArgs() const {
86   if (!SanitizerArguments.get())
87     SanitizerArguments.reset(new SanitizerArgs(*this, Args));
88   return *SanitizerArguments.get();
89 }
90 
91 StringRef ToolChain::getDefaultUniversalArchName() const {
92   // In universal driver terms, the arch name accepted by -arch isn't exactly
93   // the same as the ones that appear in the triple. Roughly speaking, this is
94   // an inverse of the darwin::getArchTypeForDarwinArchName() function, but the
95   // only interesting special case is powerpc.
96   switch (Triple.getArch()) {
97   case llvm::Triple::ppc:
98     return "ppc";
99   case llvm::Triple::ppc64:
100     return "ppc64";
101   case llvm::Triple::ppc64le:
102     return "ppc64le";
103   default:
104     return Triple.getArchName();
105   }
106 }
107 
108 bool ToolChain::IsUnwindTablesDefault() const {
109   return false;
110 }
111 
112 Tool *ToolChain::getClang() const {
113   if (!Clang)
114     Clang.reset(new tools::Clang(*this));
115   return Clang.get();
116 }
117 
118 Tool *ToolChain::buildAssembler() const {
119   return new tools::ClangAs(*this);
120 }
121 
122 Tool *ToolChain::buildLinker() const {
123   llvm_unreachable("Linking is not supported by this toolchain");
124 }
125 
126 Tool *ToolChain::getAssemble() const {
127   if (!Assemble)
128     Assemble.reset(buildAssembler());
129   return Assemble.get();
130 }
131 
132 Tool *ToolChain::getClangAs() const {
133   if (!Assemble)
134     Assemble.reset(new tools::ClangAs(*this));
135   return Assemble.get();
136 }
137 
138 Tool *ToolChain::getLink() const {
139   if (!Link)
140     Link.reset(buildLinker());
141   return Link.get();
142 }
143 
144 Tool *ToolChain::getTool(Action::ActionClass AC) const {
145   switch (AC) {
146   case Action::AssembleJobClass:
147     return getAssemble();
148 
149   case Action::LinkJobClass:
150     return getLink();
151 
152   case Action::InputClass:
153   case Action::BindArchClass:
154   case Action::CudaDeviceClass:
155   case Action::CudaHostClass:
156   case Action::LipoJobClass:
157   case Action::DsymutilJobClass:
158   case Action::VerifyDebugInfoJobClass:
159     llvm_unreachable("Invalid tool kind.");
160 
161   case Action::CompileJobClass:
162   case Action::PrecompileJobClass:
163   case Action::PreprocessJobClass:
164   case Action::AnalyzeJobClass:
165   case Action::MigrateJobClass:
166   case Action::VerifyPCHJobClass:
167   case Action::BackendJobClass:
168     return getClang();
169   }
170 
171   llvm_unreachable("Invalid tool kind.");
172 }
173 
174 Tool *ToolChain::SelectTool(const JobAction &JA) const {
175   if (getDriver().ShouldUseClangCompiler(JA))
176     return getClang();
177   Action::ActionClass AC = JA.getKind();
178   if (AC == Action::AssembleJobClass && useIntegratedAs())
179     return getClangAs();
180   return getTool(AC);
181 }
182 
183 std::string ToolChain::GetFilePath(const char *Name) const {
184   return D.GetFilePath(Name, *this);
185 
186 }
187 
188 std::string ToolChain::GetProgramPath(const char *Name) const {
189   return D.GetProgramPath(Name, *this);
190 }
191 
192 std::string ToolChain::GetLinkerPath() const {
193   if (Arg *A = Args.getLastArg(options::OPT_fuse_ld_EQ)) {
194     StringRef Suffix = A->getValue();
195 
196     // If we're passed -fuse-ld= with no argument, or with the argument ld,
197     // then use whatever the default system linker is.
198     if (Suffix.empty() || Suffix == "ld")
199       return GetProgramPath("ld");
200 
201     llvm::SmallString<8> LinkerName("ld.");
202     LinkerName.append(Suffix);
203 
204     std::string LinkerPath(GetProgramPath(LinkerName.c_str()));
205     if (llvm::sys::fs::exists(LinkerPath))
206       return LinkerPath;
207 
208     getDriver().Diag(diag::err_drv_invalid_linker_name) << A->getAsString(Args);
209     return "";
210   }
211 
212   return GetProgramPath("ld");
213 }
214 
215 
216 types::ID ToolChain::LookupTypeForExtension(const char *Ext) const {
217   return types::lookupTypeForExtension(Ext);
218 }
219 
220 bool ToolChain::HasNativeLLVMSupport() const {
221   return false;
222 }
223 
224 bool ToolChain::isCrossCompiling() const {
225   llvm::Triple HostTriple(LLVM_HOST_TRIPLE);
226   switch (HostTriple.getArch()) {
227   // The A32/T32/T16 instruction sets are not separate architectures in this
228   // context.
229   case llvm::Triple::arm:
230   case llvm::Triple::armeb:
231   case llvm::Triple::thumb:
232   case llvm::Triple::thumbeb:
233     return getArch() != llvm::Triple::arm && getArch() != llvm::Triple::thumb &&
234            getArch() != llvm::Triple::armeb && getArch() != llvm::Triple::thumbeb;
235   default:
236     return HostTriple.getArch() != getArch();
237   }
238 }
239 
240 ObjCRuntime ToolChain::getDefaultObjCRuntime(bool isNonFragile) const {
241   return ObjCRuntime(isNonFragile ? ObjCRuntime::GNUstep : ObjCRuntime::GCC,
242                      VersionTuple());
243 }
244 
245 bool ToolChain::isThreadModelSupported(const StringRef Model) const {
246   if (Model == "single") {
247     // FIXME: 'single' is only supported on ARM so far.
248     return Triple.getArch() == llvm::Triple::arm ||
249            Triple.getArch() == llvm::Triple::armeb ||
250            Triple.getArch() == llvm::Triple::thumb ||
251            Triple.getArch() == llvm::Triple::thumbeb;
252   } else if (Model == "posix")
253     return true;
254 
255   return false;
256 }
257 
258 std::string ToolChain::ComputeLLVMTriple(const ArgList &Args,
259                                          types::ID InputType) const {
260   switch (getTriple().getArch()) {
261   default:
262     return getTripleString();
263 
264   case llvm::Triple::x86_64: {
265     llvm::Triple Triple = getTriple();
266     if (!Triple.isOSBinFormatMachO())
267       return getTripleString();
268 
269     if (Arg *A = Args.getLastArg(options::OPT_march_EQ)) {
270       // x86_64h goes in the triple. Other -march options just use the
271       // vanilla triple we already have.
272       StringRef MArch = A->getValue();
273       if (MArch == "x86_64h")
274         Triple.setArchName(MArch);
275     }
276     return Triple.getTriple();
277   }
278   case llvm::Triple::aarch64: {
279     llvm::Triple Triple = getTriple();
280     if (!Triple.isOSBinFormatMachO())
281       return getTripleString();
282 
283     // FIXME: older versions of ld64 expect the "arm64" component in the actual
284     // triple string and query it to determine whether an LTO file can be
285     // handled. Remove this when we don't care any more.
286     Triple.setArchName("arm64");
287     return Triple.getTriple();
288   }
289   case llvm::Triple::arm:
290   case llvm::Triple::armeb:
291   case llvm::Triple::thumb:
292   case llvm::Triple::thumbeb: {
293     // FIXME: Factor into subclasses.
294     llvm::Triple Triple = getTriple();
295     bool IsBigEndian = getTriple().getArch() == llvm::Triple::armeb ||
296                        getTriple().getArch() == llvm::Triple::thumbeb;
297 
298     // Handle pseudo-target flags '-mlittle-endian'/'-EL' and
299     // '-mbig-endian'/'-EB'.
300     if (Arg *A = Args.getLastArg(options::OPT_mlittle_endian,
301                                  options::OPT_mbig_endian)) {
302       IsBigEndian = !A->getOption().matches(options::OPT_mlittle_endian);
303     }
304 
305     // Thumb2 is the default for V7 on Darwin.
306     //
307     // FIXME: Thumb should just be another -target-feaure, not in the triple.
308     StringRef MCPU, MArch;
309     if (const Arg *A = Args.getLastArg(options::OPT_mcpu_EQ))
310       MCPU = A->getValue();
311     if (const Arg *A = Args.getLastArg(options::OPT_march_EQ))
312       MArch = A->getValue();
313     std::string CPU =
314         Triple.isOSBinFormatMachO()
315             ? tools::arm::getARMCPUForMArch(MArch, Triple).str()
316             : tools::arm::getARMTargetCPU(MCPU, MArch, Triple);
317     StringRef Suffix =
318       tools::arm::getLLVMArchSuffixForARM(CPU,
319                                           tools::arm::getARMArch(MArch, Triple));
320     bool ThumbDefault = Suffix.startswith("v6m") || Suffix.startswith("v7m") ||
321       Suffix.startswith("v7em") ||
322       (Suffix.startswith("v7") && getTriple().isOSBinFormatMachO());
323     // FIXME: this is invalid for WindowsCE
324     if (getTriple().isOSWindows())
325       ThumbDefault = true;
326     std::string ArchName;
327     if (IsBigEndian)
328       ArchName = "armeb";
329     else
330       ArchName = "arm";
331 
332     // Assembly files should start in ARM mode.
333     if (InputType != types::TY_PP_Asm &&
334         Args.hasFlag(options::OPT_mthumb, options::OPT_mno_thumb, ThumbDefault))
335     {
336       if (IsBigEndian)
337         ArchName = "thumbeb";
338       else
339         ArchName = "thumb";
340     }
341     Triple.setArchName(ArchName + Suffix.str());
342 
343     return Triple.getTriple();
344   }
345   }
346 }
347 
348 std::string ToolChain::ComputeEffectiveClangTriple(const ArgList &Args,
349                                                    types::ID InputType) const {
350   return ComputeLLVMTriple(Args, InputType);
351 }
352 
353 void ToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
354                                           ArgStringList &CC1Args) const {
355   // Each toolchain should provide the appropriate include flags.
356 }
357 
358 void ToolChain::addClangTargetOptions(const ArgList &DriverArgs,
359                                       ArgStringList &CC1Args) const {
360 }
361 
362 void ToolChain::addClangWarningOptions(ArgStringList &CC1Args) const {}
363 
364 ToolChain::RuntimeLibType ToolChain::GetRuntimeLibType(
365   const ArgList &Args) const
366 {
367   if (Arg *A = Args.getLastArg(options::OPT_rtlib_EQ)) {
368     StringRef Value = A->getValue();
369     if (Value == "compiler-rt")
370       return ToolChain::RLT_CompilerRT;
371     if (Value == "libgcc")
372       return ToolChain::RLT_Libgcc;
373     getDriver().Diag(diag::err_drv_invalid_rtlib_name)
374       << A->getAsString(Args);
375   }
376 
377   return GetDefaultRuntimeLibType();
378 }
379 
380 ToolChain::CXXStdlibType ToolChain::GetCXXStdlibType(const ArgList &Args) const{
381   if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) {
382     StringRef Value = A->getValue();
383     if (Value == "libc++")
384       return ToolChain::CST_Libcxx;
385     if (Value == "libstdc++")
386       return ToolChain::CST_Libstdcxx;
387     getDriver().Diag(diag::err_drv_invalid_stdlib_name)
388       << A->getAsString(Args);
389   }
390 
391   return ToolChain::CST_Libstdcxx;
392 }
393 
394 /// \brief Utility function to add a system include directory to CC1 arguments.
395 /*static*/ void ToolChain::addSystemInclude(const ArgList &DriverArgs,
396                                             ArgStringList &CC1Args,
397                                             const Twine &Path) {
398   CC1Args.push_back("-internal-isystem");
399   CC1Args.push_back(DriverArgs.MakeArgString(Path));
400 }
401 
402 /// \brief Utility function to add a system include directory with extern "C"
403 /// semantics to CC1 arguments.
404 ///
405 /// Note that this should be used rarely, and only for directories that
406 /// historically and for legacy reasons are treated as having implicit extern
407 /// "C" semantics. These semantics are *ignored* by and large today, but its
408 /// important to preserve the preprocessor changes resulting from the
409 /// classification.
410 /*static*/ void ToolChain::addExternCSystemInclude(const ArgList &DriverArgs,
411                                                    ArgStringList &CC1Args,
412                                                    const Twine &Path) {
413   CC1Args.push_back("-internal-externc-isystem");
414   CC1Args.push_back(DriverArgs.MakeArgString(Path));
415 }
416 
417 void ToolChain::addExternCSystemIncludeIfExists(const ArgList &DriverArgs,
418                                                 ArgStringList &CC1Args,
419                                                 const Twine &Path) {
420   if (llvm::sys::fs::exists(Path))
421     addExternCSystemInclude(DriverArgs, CC1Args, Path);
422 }
423 
424 /// \brief Utility function to add a list of system include directories to CC1.
425 /*static*/ void ToolChain::addSystemIncludes(const ArgList &DriverArgs,
426                                              ArgStringList &CC1Args,
427                                              ArrayRef<StringRef> Paths) {
428   for (StringRef Path : Paths) {
429     CC1Args.push_back("-internal-isystem");
430     CC1Args.push_back(DriverArgs.MakeArgString(Path));
431   }
432 }
433 
434 void ToolChain::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
435                                              ArgStringList &CC1Args) const {
436   // Header search paths should be handled by each of the subclasses.
437   // Historically, they have not been, and instead have been handled inside of
438   // the CC1-layer frontend. As the logic is hoisted out, this generic function
439   // will slowly stop being called.
440   //
441   // While it is being called, replicate a bit of a hack to propagate the
442   // '-stdlib=' flag down to CC1 so that it can in turn customize the C++
443   // header search paths with it. Once all systems are overriding this
444   // function, the CC1 flag and this line can be removed.
445   DriverArgs.AddAllArgs(CC1Args, options::OPT_stdlib_EQ);
446 }
447 
448 void ToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
449                                     ArgStringList &CmdArgs) const {
450   CXXStdlibType Type = GetCXXStdlibType(Args);
451 
452   switch (Type) {
453   case ToolChain::CST_Libcxx:
454     CmdArgs.push_back("-lc++");
455     break;
456 
457   case ToolChain::CST_Libstdcxx:
458     CmdArgs.push_back("-lstdc++");
459     break;
460   }
461 }
462 
463 void ToolChain::AddCCKextLibArgs(const ArgList &Args,
464                                  ArgStringList &CmdArgs) const {
465   CmdArgs.push_back("-lcc_kext");
466 }
467 
468 bool ToolChain::AddFastMathRuntimeIfAvailable(const ArgList &Args,
469                                               ArgStringList &CmdArgs) const {
470   // Do not check for -fno-fast-math or -fno-unsafe-math when -Ofast passed
471   // (to keep the linker options consistent with gcc and clang itself).
472   if (!isOptimizationLevelFast(Args)) {
473     // Check if -ffast-math or -funsafe-math.
474     Arg *A =
475         Args.getLastArg(options::OPT_ffast_math, options::OPT_fno_fast_math,
476                         options::OPT_funsafe_math_optimizations,
477                         options::OPT_fno_unsafe_math_optimizations);
478 
479     if (!A || A->getOption().getID() == options::OPT_fno_fast_math ||
480         A->getOption().getID() == options::OPT_fno_unsafe_math_optimizations)
481       return false;
482   }
483   // If crtfastmath.o exists add it to the arguments.
484   std::string Path = GetFilePath("crtfastmath.o");
485   if (Path == "crtfastmath.o") // Not found.
486     return false;
487 
488   CmdArgs.push_back(Args.MakeArgString(Path));
489   return true;
490 }
491 
492 SanitizerMask ToolChain::getSupportedSanitizers() const {
493   // Return sanitizers which don't require runtime support and are not
494   // platform or architecture-dependent.
495   using namespace SanitizerKind;
496   return (Undefined & ~Vptr & ~Function) | CFI | CFICastStrict |
497          UnsignedIntegerOverflow | LocalBounds;
498 }
499